The last time the two Swiss friends met in the Californian desert back in 2017, Stan called Fed a very rude word. He had just lost in straight sets to the old GOAT in the final, the 20th thumping he had taken from the man he called a pal, and he was getting a bit tearful during the presentation ceremony (he was exhausted and the emotions were all getting a bit much).

Choking his way through his speech, he looked over to the Mighty Fed only to see him laughing.

“I would like to congratulate Roger,” Wawrinka said to the crowd. “He’s laughing. He’s an a**hole, but it’ OK.”

A rude word from a pal

The crowd squirmed in their seats. Was this going to be an awkward moment? Actually, no, it turned out to be perfectly fine. As Roger admitted afterwards, it was not the first time he had been referred to in such anatomical detail.

"I was trying, when he looked at me, not to give him the sad face," he said. "I was looking at him going, 'You'll be fine,' and gave him a laugh, say, maybe gets his mind off it. I guess I achieved that."

Since that day, a lot has happened to both men. Federer has gone on to win two more Grand Slam titles and, last year, regain his world No.1 ranking. Stan, meanwhile, has undergone major surgery on his left knee, surgery that could have ended his career had it not been successful. He only took his first, faltering steps on the comeback trail at the Australian Open last year.

Federer knows the danger

It has been slow and painstaking work to get back on track but now Wawrinka is back up to No.40 in the rankings and is playing like the Stan of old. But not even the old Stan had much of a chance against Fed: their career record stands at 21 wins to three in Fed’s favour. No matter, Stan is feeling good again – even if he is realistic about his record against his oldest rival – and Fed knows exactly where the dangers lie in their match-up.

“I really feel like he's been back at a normal level, let's say, around the US Open [last year],” Federer said. “But obviously his ranking was low, he was still maybe missing some fitness, you know, that day-to-day match fitness that you need, mental fitness that you require to bring it every single day. I think he was just missing it a little bit. But I think as the season wore on, he only got stronger, even though at the end he didn't play anymore because he didn't want to take a chance, which I totally understand.

“But I think, from what I'm gathering, if he's in no pain or injury-free, I think we will see a great Stan here, down the road, without a doubt, because I know what he can do. I think a lot of Stan. He's got all the different options how to win points. He's a fighter and a winner. Yeah, I hope he's going to be in the top 20, top 10 very soon again.”

Not this week, but soon Stan...

Soon, but not too soon, not if Federer has anything to do with it. He would love to see his old friend back at the top of the game but just not this week. Not in the third round of the BNP Paribas Open. Fed has plans of his own for that match and if they go according to the well-worked plan, he is aiming for his 22nd win.

In 14 years of trying, Stan has realised that his only chance against the Mighty Fed is to play him on clay – all three of his wins have come on the red stuff.

“I think maybe on clay, first my game is a bit stronger, I have a little bit more time,” Stan said. “I can use more topspin, playing more heavy on his backhand, push him more from the baseline. I think on the hard courts he can always play a little bit quicker. He can come to the net more. He can mix a little bit more. Yeah, it's always been really difficult to play him.

Missing the red stuff

“It's going to be tough match, for sure. He's the best player to ever play the sport. Stats against each other are really, really not in my favour. Yeah, I think it's great for me. “Most important is to win two matches here, to win the way I won tonight. It was tough battle, fighting, staying there physically, tennis-wise, mentally, also. Those are matches I know that can help me to get some big result.”

And if he does get that big result, maybe it will Fed’s turn to call Stan a very rude word. And maybe it will Stan’s turn to laugh.